It is now well appreciated that tumor growth necessitates the acquisition of mutations that facilitate immune evasion. Even so, tumorigenesis results in the accumulation of mutated antigens, or neoantigens, that are readily recognized by the host immune system following ex vivo stimulation. Why and how the immune system fails to recognize neoantigens are beginning to be elucidated. Groundbreaking studies by Carmi et al. (Nature, 521: 99-104 (2015)) have indicated that immune ignorance can be overcome by delivering neoantigens to activated dendritic cells via antibody-tumor immune complexes. In these studies, simultaneous delivery of tumor binding antibodies and dendritic cell adjuvants via intratumoral injections resulted in robust anti-tumor immunity. New compositions and methods for the delivery of antibodies and dendritic cell adjuvants are needed in order to reach inaccessible tumors and to expand treatment options for cancer patients and other subjects